In the practice of extrusion of billets, including hot billets or hot-lubricated billets, for example, in horizontal extrusion presses of well-known form, a reliable and adjustable mounting of the billet container and its annular holder is of critical importance so that the centerline of the container may be truly aligned and thereafter maintained in alignment with the centerline of the extrusion press as whole, and thereby a proper extrusion can be forced through the usual downstream die or die stack by a ram, dummy block thereon, or the like.
It is conventional and well-known practice to provide means such as shims, wedges, threadable bolt or jackscrew arrangements and the like to effect adjustable vertical and horizontal positioning of the support or holder for the extrusion container, and wherein the container holder is suitably guided in ways for appropriate axially limited motion of the container holder along the centerline of the press.
Hitherto, container holders have commonly been provided with angularly related, radially extending fins or ribs which would be received upon like radially oriented guideways angularly related to each other and to a horizontal plane through the press centerline. See, for example, my prior U.S. Pat. No. 4,244,205, issued Jan. 13, 1981, or Muller U.S. Pat. No. 3,350,910, issued Nov. 7, 1967.
Such angular ways may be in various locations, but typically are at about 120.degree. and 240.degree. locations (or about 4 o'clock and 8 o'clock positions) as viewed from the press centerline axis. Such mountings for the container holder were desireable in certain respects in that unavoidable thermal expansion of the press in use did not cause misalignment of the initially carefully axis-aligned holder and container inasmuch as thermal expansion of the steel press components acted substantially uniformly radially upon the radially oriented guideways for the container, and thus did not materially alter the relative position of the container with respect to the guideways and the press axis. Similarly, such angular ways did not present particular difficulty in effecting vertical adjustment of the container and holder in seeking initial axis alignment.
In contrast, however, lateral alignment thereof (i.e. right-left in a horizontal plane) with respect to the press centerline was exceedingly complex by virtue of the aforesaid radial and angular slideway support.
Further developmet in an effort to improve horizontal alignment led to the provision of similarly angularly extending fins or ribs on the holder, but which terminated in slide faces lying in a common plane parallel to a plane through the horizontal centerline of the press. Such an arrangement permitted equally ready vertical adjustment of the container holder, and furthermore permitted facile left-right or horizontal adjustment thereof to achieve axis alignment, wherein means, as a subjacent (or overhead) adjusting wedge, jackscrew or comparable means was accessibly provided as by a radially extending tongue at the 6 o'clock or 12 o'clock position on the container holder.
Such an arrangement obviated the difficulties of horizontal centerline accommodation while further enhancing easy vertical adjustment by shim or slide means or either side of the container.
While these latter improvements achieved much in the proper and precise alignment of the container with the press centerline, the same were now unable to prevent loss of alignment resulting from inescapable temperature rise and subsequent metal expansion of the container, holder, and press components generally, wherein radial expansion through the angular holder fins to the planar slide faces effected relative vertical displacement of the container with respect to the press axis.
As a consequence, an aligned container prior to heat buildup thereafter required highly difficult and indeed hazardous in-use realignment after heat-distorted shifting of the container with respect to the press axis. These aspects mitigate against the benefits obtained as to the initial ease of vertical and horizontal adjustment of the cool press.
The present invention obviates these difficulties in providing the same facile before-use press axis adjustment, while eliminating or rendering negligible any axis shift occurring from progressive thermal expansion of hot press components during press operation.